1. Field of the Invention
The present invention relates to an image processing apparatus and method and, more particularly, to an image processing apparatus and method in which one pixel of input multi-level data is converted into a plurality of pixels of binary data and output.
2. Description of Related Art
In an image processing apparatus such as a dot printer for outputting binary data, jaggies appear in a character or an oblique line. To minimize the jaggies, an input pixel is converted (divided) into a plurality of pixels and output.
Of the plurality of converted pixels, pixels to be output as black pixels (significant pixels) are determined in accordance with a pattern which is recognized by pattern matching with a predetermined pattern including peripheral pixels and held in advance.
However, the above technique has the following problems. When the input image is a multi-level image, the number of predetermined patterns necessary for pattern matching is very large. Therefore, when one pixel of the input multi-level image is to be converted into a plurality of binary pixels, the processing time increases as compared to a case wherein a binary image is input. In addition, since the capacity of a memory for holding the large number of predetermined patterns increases, the cost increases accordingly.